The invention involves a vehicle with an apparatus to incline the chassis in curves versus its undercarriages, which rotate versus the chassis around vertical axes. We know that rail tracks are elevated in curves in order to balance, at least partially, the centrifugal forces arising in the vehicle. The installation of such elevations, however, is rather involved. Therefore, vehicles have been developed which, when passing through curves, incline the chassis toward the inside of the curve. U.S. Pat. No. 3,717,104 discloses an apparatus wherein a centrifugal meter places the chasis at a slant versus the undercarriage via a hydraulic control device. This expenditure may be justified for big railroad cars, but not for small vehicles.
It is the object of the present invention to provide a simple device to tilt the chassis versus its undercarriage during curves. This is done by providing, between neighboring undercarriage parts where the longitudinal distance changes while passing through a curve, a device which transforms the change in distance into a movement tilting the chassis towards the inside of the curve. When passing a curve, the distance between the undercarriage decreases on the inside of the curve and increases on the outside of the curve. This change in distance is, without great expenditure, used to tilt the chassis versus the undercarriages, one of which is a swivel base. Thus, it is possible to have a device to incline the chassis versus its undercarriages using simple means. The tracks do not require expensive elevations in curves and can simply be arranged horizontally. The undercarriages are interconnected by means of a distancing bar in the longitudinal center axis of the vehicle.
According to another detail of the invention, the device consists of toggle levers hinged between front and rear undercarriages on each side of the vehicle while the connecting points of each toggle levers are joined with the chassis. When passing through a curve, the distances change between the terminal points of the toggle levers. The connecting point of the toggle lever on the inside of the curve is pressed down, if arranged accordingly, thus transmitting this movement to the chassis, which is raised on the outside of the curve by the toggle lever arranged there, as the terminal points of the toggle lever have experienced a change (i.e. increase) in distance.
Since the chassis is very often supported on the undercarriages via springs, this has to be taken into consideration in the tilting apparatus. Therefore, a cross stabilizer is arranged between the connecting points of the toggle levers and the chassis. This consists of a bar with angled extensions on both ends, whose central cross bar portion pivots in bushings at the sides of the chassis and whose pendulum leg ends are flexibly joined to the connecting points of the toggle levers. When there are spring movements by the chassis versus the undercarriage the cross stabilizer turns in its bearings. It is in itself non-rotatable and is lifted on one side and lowered on the other side during curves and transmits this movement to the chassis. Between the terminal points of the pendulum legs of the cross stabilizer and the connecting points of the toggle levers, intermediate bars may be provided which permit relative movements in longitudinal and lateral direction of the vehicle between the connecting points of the toggle levers and the terminal points and the pendulum legs.
If the springs are arranged between axles and undercarriages and the chassis rests on the undercarriages without springs, the apparatus may consist of a pole firmly attached to one undercarriage and equipped with ropes which lead to fixed points in the chassis around pulleys arranged vertically on the sides of the other undercarriage. In order to achieve the desired incline, the pole may project into the neighboring undercarriage. Likewise, the apparatus may consist of two tension ropes or the like, which are respectively attached to the diagonally opposite ends of the neighboring undercarriages, lead roughly in a straight line to the neighboring undercarriage and from there around a first horizontal pulley and a second vertical pulley arranged on the other side of the undercarriage, from where the ropes go to a fixed point in the chassis.
The apparatus may also consist of a pressure medium system with at least two working cylinder chambers arranged between the neighboring undercarriages and at least one piston movable by one of the undercarriages during the passage of curves. The working cylinder chamber increasing during curves is connected to a lift cylinder arranged on the inside of the curve between undercarriage and chassis, facilitating the lowering of the chassis, and the working cylinder chamber decreasing in curves is connected to a lift cylinder arranged on the outside of the curve between undercarriage and the chassis, effecting an elevation of the chassis, each via a pressure medium line. The desired lift may be achieved by means of synchronizing the cylinder diameters.
The working cylinder chambers may be arranged in one common cylinder shell, separated from each other by the piston, whereby the cylinder shell is attached to one undercarriage and the piston to the other undercarriage. It is also possible to arrange two working cylinder chambers in two different cylinder shells on both sides of the longitudinal axis of the vehicle, each provided with a piston. The lift cylinders and their pistons are arranged between one of the undercarriages and the chassis with vertical direction of movement.
Several examples of the invention are shown on the drawings and explained as follows: